1*9280e99dSMatt Turner // SPDX-License-Identifier: GPL-2.0
2*9280e99dSMatt Turner
3*9280e99dSMatt Turner #include <linux/bits.h>
4*9280e99dSMatt Turner #include <linux/perf_event.h>
5*9280e99dSMatt Turner #include <linux/sched/task_stack.h>
6*9280e99dSMatt Turner #include <asm/perf_regs.h>
7*9280e99dSMatt Turner
8*9280e99dSMatt Turner #define REG(idx, field) \
9*9280e99dSMatt Turner [PERF_REG_ALPHA_##idx] = offsetof(struct pt_regs, field)
10*9280e99dSMatt Turner
11*9280e99dSMatt Turner #define REG_RESERVED (~GENMASK_ULL(PERF_REG_ALPHA_MAX - 1, 0) | \
12*9280e99dSMatt Turner GENMASK_ULL(PERF_REG_ALPHA_R15, PERF_REG_ALPHA_R9))
13*9280e99dSMatt Turner
14*9280e99dSMatt Turner static const unsigned int pt_regs_offset[PERF_REG_ALPHA_MAX] = {
15*9280e99dSMatt Turner REG(R0, r0), REG(R1, r1), REG(R2, r2), REG(R3, r3),
16*9280e99dSMatt Turner REG(R4, r4), REG(R5, r5), REG(R6, r6), REG(R7, r7),
17*9280e99dSMatt Turner REG(R8, r8), REG(R16, r16), REG(R17, r17), REG(R18, r18),
18*9280e99dSMatt Turner REG(R19, r19), REG(R20, r20), REG(R21, r21), REG(R22, r22),
19*9280e99dSMatt Turner REG(R23, r23), REG(R24, r24), REG(R25, r25), REG(R26, r26),
20*9280e99dSMatt Turner REG(R27, r27), REG(R28, r28), REG(GP, gp), REG(PC, pc),
21*9280e99dSMatt Turner };
22*9280e99dSMatt Turner
perf_reg_value(struct pt_regs * regs,int idx)23*9280e99dSMatt Turner u64 perf_reg_value(struct pt_regs *regs, int idx)
24*9280e99dSMatt Turner {
25*9280e99dSMatt Turner if (idx == PERF_REG_ALPHA_SP) {
26*9280e99dSMatt Turner if (user_mode(regs))
27*9280e99dSMatt Turner return user_stack_pointer(regs);
28*9280e99dSMatt Turner /*
29*9280e99dSMatt Turner * Software events built by perf_fetch_caller_regs() use a
30*9280e99dSMatt Turner * per-CPU pt_regs rather than a trap frame, and pt_regs has
31*9280e99dSMatt Turner * nowhere to record sp, so report none.
32*9280e99dSMatt Turner */
33*9280e99dSMatt Turner if (!object_is_on_stack(regs))
34*9280e99dSMatt Turner return 0;
35*9280e99dSMatt Turner /* Same kernel sp approximation as stacktrace.c. */
36*9280e99dSMatt Turner return (unsigned long)(regs + 1);
37*9280e99dSMatt Turner }
38*9280e99dSMatt Turner
39*9280e99dSMatt Turner if (WARN_ON_ONCE((u32)idx >= PERF_REG_ALPHA_MAX ||
40*9280e99dSMatt Turner BIT_ULL(idx) & REG_RESERVED))
41*9280e99dSMatt Turner return 0;
42*9280e99dSMatt Turner
43*9280e99dSMatt Turner return *(unsigned long *)((void *)regs + pt_regs_offset[idx]);
44*9280e99dSMatt Turner }
45*9280e99dSMatt Turner
perf_reg_validate(u64 mask)46*9280e99dSMatt Turner int perf_reg_validate(u64 mask)
47*9280e99dSMatt Turner {
48*9280e99dSMatt Turner if (!mask || mask & REG_RESERVED)
49*9280e99dSMatt Turner return -EINVAL;
50*9280e99dSMatt Turner
51*9280e99dSMatt Turner return 0;
52*9280e99dSMatt Turner }
53*9280e99dSMatt Turner
perf_reg_abi(struct task_struct * task)54*9280e99dSMatt Turner u64 perf_reg_abi(struct task_struct *task)
55*9280e99dSMatt Turner {
56*9280e99dSMatt Turner return PERF_SAMPLE_REGS_ABI_64;
57*9280e99dSMatt Turner }
58*9280e99dSMatt Turner
perf_get_regs_user(struct perf_regs * regs_user,struct pt_regs * regs)59*9280e99dSMatt Turner void perf_get_regs_user(struct perf_regs *regs_user,
60*9280e99dSMatt Turner struct pt_regs *regs)
61*9280e99dSMatt Turner {
62*9280e99dSMatt Turner regs_user->regs = task_pt_regs(current);
63*9280e99dSMatt Turner regs_user->abi = perf_reg_abi(current);
64*9280e99dSMatt Turner }
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